This is now ready for review: it considers kernels, terminals and API activity, so it shouldn't shut the server down if you're still doing anything.

You could configure it like this:

c.MappingKernelManager.cull_idle_timeout=600c.NotebookApp.shutdown_no_activity_timeout=600

With those options, if you close a notebook tab leaving the kernel running, it will cull the kernel after 10 minutes. After another 10 minutes, if you haven't done anything else, the server will shut down.

There is currently no option to cull idle terminals, so if you leave a terminal open, the server will never shut down. We could add an option for that separately.

@Carreau@gnestor@minrk ?

Makes sense. Only thing I'd like to add is that there's already an API endpoint for retrieving activity info inservices/api/handlers.py. It would be good to get this updatedlast_activity to the field reported there, as well, so the two stay in sync. I'm not sure what that means wrt where the last_last_activity calculation belongs. At the app level makes sense, but at the same time accessing a method on the app object from a handler doesn't seem right.

@minrk To clarify: Does thelast_activity provided byservices/api/handlers.py include kernel and terminal activity? Can the app get thelast_activity value from there? That would simplify this quite a bit 👍

@gnestor it should be the last activity of any kind on the server as a whole i.e. exactly the same value added here inapp.last_activity.

It doesn't currently include terminals, because I only added terminal activity timestamps in this PR. I'll look for a way to unify them.

I have unified them in a method on the web application object. This seemed a good compromise, as it's easily accessible both from theNotebookApp and from the API handler.

@minrk Care to take one last look and merge?